Time switch



April 30, 1940. ,3 MOHR I 2,199,184

TIME SWITCH I Filed 0612. 16, 1939 INVENTOR Z0 BY ATTORNEY Patented Apr. 30, 1 940 I UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to time switches and has for an object to provide a switch mechanism for automatically starting and stopping the motor of a heater at predetermined time intervals.

A further object of the invention is to provide a switch including a time controlled dial having a circular series of openings adapted to selectively receive pins disposed in the path. of circuit make-and-break levers of a mercury switch, the make-and-break levers being positively operated in sequence by a pair of the pins disposed in pre-determined openings to turn on and turn off the current continuously at pre-determined time intervals so that the heater will be intermittently operated during these intervals.

A further object is to provide a device of this character which will be formed of a few strong simple and durable parts, which will be inexpensive to manufacture, and which will not easily get out of order.

With the above and other objects in view the invention consists of certain novel details of construction and combinations of parts hereinafter fully described and claimed, it being understood that various modifications may be resorted to within the scope of the appended claims without departing from the spirit or sacrificing any of the advantages of the invention.

In the accompanying drawing forming a part of this specification:

Figure l is a front elevation of a time switch constructed in accordance with the invention.

Figure 2 is a side elevation of the switch shown in Figure 1.

Figure 3 is a side elevation of the switch make-and-break levers and showing the pivot thereof and also the stop for limiting movement of the levers in one direction.

Referring now to the drawing in which like characters of reference designate similar parts in the various views, I designates a frame plate to the rear side of which is secured a conventional clock I! which may be either a mechanical clock or an electric clock. The shaft |2 of the minute hand of the clock is extended through the plate l0 and is equipped with a dial I3. The dial is removably secured to the shaft by a nut M which is threaded on to a reduced threaded end l5 of the shaft.

The dial is provided with a circular series of openings l6 arranged at five minute intervals apart concentric with the shaft l2. These openings are threaded to interchangeably receive threaded pins l1 and 8. Certain of the pins project from the back of the dial and certain of the pins project'from the front of the dial to be intercepted by respective make-and-break levers of switch mechanism which will now be described.

A switch H! of the mercury type, is secured by a spring clip 2% to the lower end of a lever 2| which is pivoted between its end to the plate H] at a point below the dial by a pivot pin 22, as best shown in Figure 3. The upper end 23 of the lever is arranged in rear of the dial in the path of movement of the pins H which projects from the rear face of the dial.

A second lever 24 is connected at its lower end to the pivot pin 22, and boss 25 on the lever 2| receives the pivot pin and spaces the lever 24 from the lever 2|. The upper end 26 of the lever 24 is disposed in front of the dial l3 in the path of the pins i8 which projects from the front face of the dial.

A stop pin 27 projects from the plate l0 and limits rocking movement ofboth levers 24 and 2| in one direction.

A rocker it is pivoted between its ends to the plate |El laterally of the levers 2| and 24 by a pivot pin 2?}. The upper end of the rocker is connected by a link 30 to the lever 2| above the pivot pin 22 of the lever. Likewise the lower end of the rocker is connected by a link 3| to the lever 24 above the pivot pin 23.

In operation any number of such pins l1 and it are arranged in a pattern on the dial so as to indicate predetermined time intervals at which the switch is to be turned on and turned off. When the lever 2| is moved from the position shown in Figure 1 to its opposite limit of movement by the dial pin- H on the rear face of the dial the switch l9 is tilted to allow the mercury to run over to the opposite end of the tube from that shown in Figure 1 to circuit breaking position. At this time the link 30 moves the rocker 29 to move the link 3| and push the lever 24 back to its starting position against the stop pin 27 to await engagement by the pin |8 on the front face of the dial. When the lever 24 contacts with the pin 8, the reverse of the movements above described in connection with the lever 23 is effected, and the mercury tube I9 is tilted to permit the mercury to flow to the switch contact carrying end of the tube to circuit closing position.

From the above description it is thought that the construction and operation of the invention will be fully understood without further explanation.

What is claimed is:

1. A time switch comprising a clock driven dial provided with an annular series of openings concentric with the axis of the dial, pins interchangeably received in the openings and pro jecting from the front and rear faces of the dial, a pair of levers pivoted on a common axis, a mercury switch carried by one of the levers, said levers being arranged respectively to engage pins on the front and rear of the dial to open and close the switch, and link motion mechanism connected to said levers and adapted to reset one of the levers when the other lever is moved to operative position by said pins.

2. A time switch comprising a clock, a shaft driven by the clock to make one revolution per hour, a dial removably secured to the shaft and provided with a circular series of openings arranged at five-minute intervals apart concentrically with the shaft, pins interchangeably engaged with the openings and projecting from the front and rear faces of the dial, a lever pivoted intermediate its ends at a point below the dial, a mercury switch carried by the lower end of the lever, the upper end of the lever being disposed in the path of the pins in rear of the dial, a second lever pivoted at its lower end to the pivot of the first named lever, the upper end of the second named lever being disposed in the path of the pins on the front of the dial, a rocker pivoted between its ends laterally of the levers, a link connecting the upper end of the rocker to the first named lever above the pivot of the lever, and a link connecting the lower end of the rocker to the second named lever above the pivot er the lever, operation of the first named lever by a dial pin opening the switch and operation of the second lever by a dial pin closing the switch.

CHARLES B. MOHR. 

